Substrate processing apparatus

ABSTRACT

A plasma supply unit includes a first conductive portion, a second conductive portion having at least a part extending to overlap the first conductive portion, and a ground shield located between the first conductive portion and the second conductive portion, and a substrate processing apparatus including the plasma supply unit.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of Korean Patent Application No.10-2017-0110341, filed on Aug. 30, 2017, in the Korean IntellectualProperty Office, the disclosure of which is incorporated herein in itsentirety by reference.

BACKGROUND 1. Field

One or more embodiments relate to a substrate processing apparatus, andmore particularly, to a substrate processing apparatus for processing asubstrate by using a plasma process.

2. Description of the Related Art

As sizes of semiconductor devices have continuously decreased, the needfor more precise control of thin film deposition at lower temperatureshas been raised. Accordingly, a plasma process such as plasma-enhancedatomic layer deposition (PEALD) has been suggested and an applicationrange of the plasma process has been continuously expanded.

In a plasma process, a reacting gas decomposes into radicals due toplasma. Accordingly, it is necessary to stably and precisely controlplasma in the reaction space. As a size of a substrate has increased,various methods have been used to uniformly generate plasma in areaction space over the substrate. For example, a radical concentrationper unit volume in a reaction space may be maintained at a relativelyuniform level by providing a plurality of radio frequency (RF) rods thatsupply plasma power (e.g., RF power) to a plasma electrode.

SUMMARY

One or more embodiments include a substrate processing apparatus wheremore uniform plasma supply and more uniform thin film quality isachieved in a plasma processing process using high frequency plasmaequal to or greater than 60 MHz so as to deposit a thin film with higherquality.

One or more embodiments include a substrate processing apparatus forpreventing the density of plasma generated in a reaction space frombeing not uniform due to cross-talk between plasma currents flowingthrough plasma conductors such as radio frequency (RF) rods and thequality of a thin film processed on a substrate from being not constant.

One or more embodiments include a substrate processing apparatus foruniformly applying plasma in a substrate processing process of applyinghigh-frequency plasma having a frequency equal to or greater than 60 MHzto deposit a high-quality thin film and achieving high uniformity of athin film.

Additional aspects will be set forth in part in the description whichfollows and, in part, will be apparent from the description, or may belearned by practice of the presented embodiments.

According to one or more embodiments, a substrate processing apparatusincludes: a reactor; a gas supply unit located in the reactor; and aplasma supply unit electrically connected to the gas supply unit,wherein the plasma supply unit includes: a first conductive portion; asecond conductive portion extending to overlap at least a part of thefirst conductive portion; and a ground shield located between the firstconductive portion and the second conductive portion.

The second conductive portion may extend to the gas supply unit so thatthe second conductive portion and the gas supply unit are electricallyconnected to each other.

The substrate processing apparatus may further include: a radiofrequency (RF) rod extending to the first conductive portion toelectrically connect to the first conductive portion; and a coversurrounding the RF rod and electrically connected to the reactor,wherein an induced signal component generated by at least one of thefirst conductive portion and the second conductive portion flows throughthe ground shield, the reactor, and the cover.

The substrate processing apparatus may further include at least onemetal member configured to mechanically fix the ground shield to thereactor.

The ground shield may have a plate-like structure, and may include atleast one through-hole through which the first conductive portion andthe second conductive portion are connected to each other.

The ground shield may have an annular disk shape with a central hole,wherein a gas inlet connected to the gas supply unit is located throughthe central hole of the ground shield.

According to one or more embodiments, a substrate processing apparatusincludes: a gas inlet; a gas supply unit connected to the gas inlet; anda plasma supply unit electrically connected to the gas supply unit,wherein the plasma supply unit includes: a plasma generator; a radiofrequency (RF) rod connected to the plasma generator; a bridge connectedto the RF rod and extending to surround the gas inlet; a plurality offeeds located symmetric about the gas inlet; and a split pointconfigured to connect the bridge to the plurality of feeds.

The plurality of feeds may include: a first feed having at least a partextending to overlap a first end portion of the bridge; a second feedextending in a direction opposite to a direction in which the first feedextends; a third feed having at least a part extending to overlap asecond end portion of the bridge; and a fourth feed extending in adirection opposite to a direction in which the third feed extends.

The plasma supply unit may further include a ground shield locatedbetween the bridge and the plurality of feeds.

According to one or more embodiments, a substrate processing apparatusincludes a plasma supply unit, wherein the plasma supply unit includes:a plasma generator; a radio frequency (RF) rod; a bridge; a split point;a plurality of feeds; and a ground shield located between the bridge andthe plurality of feeds, wherein the plasma supply unit is connected toan upper portion of a reactor.

The RF rod and the bridge may be connected to each other, the bridge andthe plurality of feeds may be connected to each other at the splitpoint, and an RF current generated by the plasma generator may besupplied to the reactor through the RF rod, the bridge, the split point,and the plurality of feeds.

The plurality of feeds may be located symmetric about a center of thesubstrate processing apparatus.

The ground shield may include a metal. The ground shield may includealuminum.

The ground shield may be configured to prevent cross-talk occurringbetween the bridge and the plurality of feeds.

The plasma generator may be configured to generate plasma having afrequency equal to or greater than 60 MHz.

The substrate processing apparatus may further include a gas inletlocated between the plurality of feeds connected to the upper portion ofthe reactor, wherein the bridge bypasses the gas inlet.

BRIEF DESCRIPTION OF THE DRAWINGS

These and/or other aspects will become apparent and more readilyappreciated from the following description of the embodiments, taken inconjunction with the accompanying drawings in which:

FIG. 1 is a cross-sectional view of a substrate processing apparatusaccording to embodiments;

FIGS. 2 and 3 are schematic views of substrate processing apparatusesaccording to embodiments;

FIG. 4A is a perspective view illustrating a part of a plasma supplyunit where four conductive structures are located symmetric about areactor of a substrate processing apparatus;

FIG. 4B is a perspective view illustrating a state where cross-talkoccurs between the conductive structures of FIG. 4A;

FIG. 5 illustrates results of an experiment about uniformity of asilicon oxide film performed in each condition and a radio frequency(RF) electric field (E-field) distribution according to an arrangementof conductive structures for transferring plasma;

FIG. 6 is a perspective view of a plasma supply unit including 4 feed RFrods and a ground shield;

FIG. 7 is a perspective view illustrating only the ground shield of FIG.6;

FIG. 8 is a schematic view of a substrate processing apparatus accordingto embodiments; and

FIG. 9 is a detailed view illustrating a plasma supply unit of thesubstrate processing apparatus of FIG. 8.

DETAILED DESCRIPTION

The present disclosure will now be described more fully with referenceto the accompanying drawings, in which embodiments of the invention areshown.

The present disclosure may, however, be embodied in many different formsand should not be construed as being limited to the embodiments setforth herein; rather, these embodiments are provided so that thisdisclosure will be thorough and complete, and will fully convey theconcept of the present disclosure to one of ordinary skill in the art.

The terminology used herein is for the purpose of describing embodimentsonly and is not intended to be limiting of embodiments of the presentdisclosure. As used herein, the singular forms “a”, “an”, and “the” areintended to include the plural forms as well, unless the context clearlyindicates otherwise. It will be further understood that the terms“comprises”, and/or “comprising” used herein specify the presence ofstated features, integers, steps, operations, members, components,and/or groups thereof, but do not preclude the presence or addition ofone or more other features, integers, steps, operations, members,components, and/or groups thereof. As used herein, the term “and/or”includes any and all combinations of one or more of the associatedlisted items.

It will be understood that, although the terms first, second, third etc.may be used herein to describe various members, regions, layers, and/orsections, these members, regions, layers, and/or sections should not belimited by these terms. For example, these terms do not limit thesequence and/or importance of the corresponding elements. These termsare only used to distinguish one member, region, or section from anothermember, region, or section. Thus, a first member, region, or sectiondiscussed below could be termed a second member, region, or sectionwithout departing from the teachings of embodiments.

The present disclosure will now be described with reference to theaccompanying drawings, in which embodiments are shown. Variations fromthe shapes of the illustrations as a result, for example, ofmanufacturing techniques and/or tolerances, are to be expected. Thus,embodiments should not be construed as limited to the particular shapesof regions illustrated herein but may be to include deviations in shapesthat result, for example, from manufacturing.

Expressions such as “at least one of”, when preceding a list ofelements, modify the entire list of elements and do not modify theindividual elements of the list.

Although a substrate processing apparatus described in the presentspecification may be a semiconductor or display substrate depositionapparatus, the present disclosure is not limited thereto. The substrateprocessing apparatus may refer to any apparatus needed to deposit amaterial for forming a thin film or an apparatus in which a raw materialfor etching or polishing a material is uniformly supplied. The followingwill be described on the assumption that the substrate processingapparatus is a semiconductor deposition apparatus for convenience ofexplanation.

FIG. 1 is a cross-sectional view of a substrate processing apparatusaccording to embodiments.

Referring to FIG. 1, the substrate processing apparatus may include areactor 1, a gas inlet (not shown), a gas supply unit 3, and a plasmasupply unit P.

The reactor 1 that is a structure for forming a reaction space forprocessing a substrate may include at least one partition wall. The gasinlet (not shown) for supplying a gas to the gas supply unit 3 may beprovided in the partition wall. For example, the gas inlet may be athrough-hole formed in the partition wall or a pipe located in thethrough-hole. When the substrate processing apparatus is an atomic layerdeposition apparatus, a source gas, a purge gas, and/or a reacting gasmay be supplied through the gas inlet. The gas inlet may be located atthe center of the reaction space, may be located on a side of thereaction space, or may be located at both the center and on a side ofthe reaction space.

The gas supply unit 3 may be located in the reactor 1 and may beconfigured to supply a gas to an object to be processed in the reactionspace. The gas supply unit 3 may be implemented as a horizontalflow-type unit, a shower head-type unit, or an appropriate unit forsupplying a gas into the reaction space. The gas supply unit 3 may be aconductor. Accordingly, when the substrate processing apparatus is aplasma atomic layer deposition apparatus, the gas supply unit 3 mayfunction as an electrode for applying plasma.

The plasma supply unit P may be electrically connected to the gas supplyunit 3. For example, the plasma supply unit P may include a firstconductive portion C1 and a second conductive portion C2, and one endportion of the second conductive portion C2 may extend to the gas supplyunit 3 so that the second conductive portion C2 and the gas supply unit3 are electrically connected to each other. Accordingly, power appliedfrom the plasma supply unit P may be transferred to the gas supply unit3, and the gas supply unit 3 located in the reactor 1 may apply plasmainto the reaction space.

The first conductive portion C1 and the second conductive portion C2 mayextend to overlap each other. For example, the first conductive portionC1 and the second conductive portion C2 may extend in a first direction(e.g., an H direction) to be parallel to each other, and the firstconductive portion C1 and the second conductive portion C2 may overlapeach other in a second direction (e.g., a V direction) different fromthe first direction. In an optional embodiment, a direction of a firstcurrent I₁ flowing through the first conductive portion C1 and adirection of second currents I_(E1) and I_(E2) flowing through thesecond conductive portion C2 may be the same or different from eachother.

The plasma supply unit P may further include a ground shield GS locatedbetween the first conductive portion C1 and the second conductiveportion C2. The ground shield GS may have a plate-like structure, andmay be formed of a metal material. In an embodiment, the ground shieldGS may be formed of aluminum. In an optional embodiment, the groundshield GS may include at least one through-hole T through which thefirst conductive portion C1 and the second conductive portion C2 areconnected to each other. For example, the first conductive portion C1and the second conductive portion C2 may be connected to each other by abranch portion D, and the branch portion D may extend through thethrough-hole T of the ground shield GS.

The second conductive portion C2 may include a first extending portionE1 and a second extending portion E2 extending in opposite directionsfrom the first extending portion E1. The first extending portion E1 mayextend to overlap the first conductive portion C1. Accordingly, adirection of the first current I₁ flowing through the first conductiveportion C1 and a direction of the second current I_(E1) flowing throughthe first extending portion E1 of the second conductive portion C2 maybe opposite to each other, and the direction of the first current I₁flowing through the first conductive portion C1 and a direction of thesecond current I_(E2) flowing through the second extending portion E2 ofthe second conductive portion C2 may be the same.

Since the second current I_(E2) flowing through the second extendingportion E2 of the second conductive portion C2 flows in the samedirection as that of the first current I₁ flowing through the firstconductive portion C1, cross-talk between currents may not occur andthus there is no problem in transferring power. However, since thesecond current I_(E1) flowing through the first extending portion E1 ofthe second conductive portion C2 flows in a direction opposite to thatof the first current I₁ flowing through the first conductive portion C1,cross-talk between currents may occur. Accordingly, the plasma powertransferred to the first extending portion E1 may be less than plasmapower transferred to the second extending portion E2.

In order to prevent cross-talk between currents and power reduction, theground shield GS may be located between the first conductive portion C1and the second conductive portion C2. For example, when the firstconductive portion C1 and the second conductive portion C2 overlap eachother and currents flow in different directions, an induced signalcomponent generated by the currents may be discharged through the groundshield GS, and thus cross-talk due to the currents and the inducedsignal component generated by the currents may be prevented.

In an optional embodiment, the ground shield GS may be electricallyconnected to the reactor 1. Accordingly, the induced signal componentgenerated by at least one of the first conductive portion C1 and thesecond conductive portion C2 may be discharged to the outside throughthe ground shield GS and the reactor 1.

For example, a radio frequency (RF) rod R extending from a plasmagenerator G to the first conductive portion C1 may be located on thereactor 1. Also, a cover CV electrically connected to the reactor 1 maybe located to surround the RF rod R. In this case, the induced signalcomponent generated by at least one of the first conductive portion C1and the second conductive portion C2 may flow through the ground shieldGS, the reactor 1, and the cover CV.

In order to mechanically and/or electrically connect the ground shieldGS to the reactor 1, the ground shield GS and the reactor 1 may beformed to contact each other. For example, the reactor 1 may extend sothat a surface of the reactor 1 contacts a bottom surface of the groundshield GS having a plate-like structure. In an optional embodiment, thesubstrate processing apparatus may further include a metal member M, andthe metal member M may pass through the ground shield GS and may befixed to the reactor 1 so that the ground shield GS contacts the reactor1. For example, the metal member M may be a metal bolt. The groundshield GS may be mechanically fixed to the reactor 1 by the metal memberM, and as a result, the ground shield GS and the reactor 1 may beelectrically connected to each other to form a ground channel.

FIGS. 2 and 3 are schematic views of substrate processing apparatusesaccording to embodiments. The substrate processing apparatuses accordingto these embodiments may be modifications of the substrate processingapparatus of the previous embodiments. Accordingly, a repeateddescription between the embodiments will not be given.

Referring to FIG. 2, the reactor 1 may be a substrate processingapparatus for an in-situ plasma process for generating plasma in areaction space 5 between two electrodes (i.e., a first electrode by thegas supply unit 3 and a second electrode by a substrate support 4). Thegas supply unit 3 may be a shower head-type unit, and may supply a gasintroduced through a gas inlet 2 to the reaction space 5 formed betweenthe gas supply unit 3 and the substrate support 4.

The gas supply unit 3 may include an RF rod 10 formed on a surface ofthe gas supply unit 3, and the RF rod 10 may be connected to a matchingnetwork 9 and a plasma generator 8 for a plasma process. The plasmagenerator 8 may be an RF generator, and plasma power generated by theplasma generator 8 may be supplied through the matching network 9 andthe RF rod 10 to the gas supply unit 3. The gas supply unit 3 may act asan electrode, and may decompose a gas in the reaction space 5 togenerate plasma, and may induce a chemical reaction over a substrate(not shown).

In FIG. 3 illustrating a substrate processing apparatus according toother embodiments, a plurality of RF rods (e.g., 10 and 11) are locatedsymmetric about the gas inlet 2. The gas inlet 2 may be formed as a pipelocated in a through-hole formed in a partition wall of the reactor 1,or may be formed as a partition wall structure (i.e., the through-hole)of the reactor 1. When the gas supply unit 3 is a shower head-type unit,since the gas inlet 2 is located at the center of the reactor 1, an RFrod that transfers plasma power to the gas supply unit 3 may not belocated at the center of the gas supply unit and is located on a side ofthe gas supply unit 3 (see FIG. 2).

Considering the fact that plasma power is non-uniformly applied into thereaction space 5 due to an RF rod located on a side, a plurality of RFrods are located symmetric about the center of the reactor 1 in FIG. 3.The number of RF rods may be increased to 2, 4, etc. Since the RF rodsare symmetrically located, the problem that plasma power isnon-uniformly applied into the reaction space 5 due to an asymmetricarrangement of RF rods may be solved.

The terms “RF rods” used herein refer to a series of conductivestructures located between a plasma supply unit (e.g., a plasmagenerator and/or a matching network) and the gas supply unit and the “RFrods” themselves have no unique positions or shapes. Also, althoughvarious terms are used to describe conductive structures such as“bridge”, “feed”, and “feed RF rod” as well as “RF rod” in the detaileddescription and the claims, the terms may be interchangeably used.

FIG. 4A is a perspective view illustrating a state where four conductivestructures are located symmetric about a reactor. FIG. 4B is aperspective view illustrating a state where cross-talk occurs betweenthe conductive structures of FIG. 4A.

Referring to FIG. 4A, a plasma supply unit may include an RF rod 15, abridge 16, first and second split points 17 and 18, a first feed 19, asecond feed 20, a third feed 21, a fourth feed 22, and feed RF rods Frespectively connected to the first through fourth feeds 19 through 22.The first through fourth feeds 19 through 22 may be connected to a gassupply unit (not shown) through the feed RF rods F. The first feed 19and/or the second feed 20 and the third feed 21 and/or the fourth feed22 may be symmetric to each other about the reactor. Likewise, the feedRF rods F may be symmetric about the reactor. Accordingly, theuniformity of plasma generated in a reaction space may be improved.

The RF rod 15 may be connected to a plasma generator (not shown). Theplasma generator may be configured to generate plasma having a frequencyequal to or greater than 60 MHz. The bridge 16 may be connected to theRF rod 15. The bridge 16 may extend to surround a part of the gas inlet2 (see FIG. 9). The first through fourth feeds 19 through 22 may belocated symmetric about the gas inlet 2. Also, the feed RF rods F may belocated symmetric about the gas inlet 2. Accordingly, the gas inlet 2may be located between the first through fourth feeds 19 through 22connected to an upper portion of the reactor and/or between the feed RFrods F connected to the upper portion of the reactor.

The first and second split points 17 and 18 may be configured to connectthe bridge 16 and the first through fourth feeds 19 through 22. Forexample, the first feed 19 and the second feed 20 may be connected tothe bridge 16 through the first split point 17. Also, the third feed 21and the fourth feed 22 may be connected to the bridge 16 through thesecond split point 18.

The bridge 16 may include a linear extending portion 16A extending fromthe RF rod 15 and first and second peripheral extending portions 16B and16C extending from the linear extending portion 16A to surround at leasta part of the gas inlet 2 by bypassing the gas inlet 2 (see FIG. 9). Thefirst and second peripheral extending portions 16B and 16C may includethe first peripheral extending portion 16B extending by 90°counterclockwise about the center of the reactor (or the gas inlet 2)from the linear extending portion 16A and the second peripheralextending portion 16C extending by 90° clockwise about the center of thereactor (or the gas inlet 2) from the linear extending portion 16A.

The first peripheral extending portion 16B may be connected to the firstfeed 19 and the second feed 20 through the first split point 17. Atleast a part of the first feed 19 may overlap an end portion of thebridge 16. For example, the first peripheral extending portion 16B ofthe bridge 16 may extend by 90° counterclockwise, and an end portion ofthe bridge 16 extending by 90° counterclockwise may overlap the firstfeed 19. The second feed 20 may extend in a direction opposite to adirection in which the first feed 19 extends.

The second peripheral extending portion 16C may be connected to thethird feed 21 and the fourth feed 22 through the second split point 18.At least a part of the third feed 21 may overlap another end portion ofthe bridge 16. For example, the second peripheral extending portion 16Cof the bridge 16 may extend by 90° clockwise, and another end portion ofthe bridge 16 extending by 90° clockwise may overlap the third feed 21.The fourth feed 22 may extend in a direction opposite to a direction inwhich the third feed 21 extends.

Referring to FIG. 4B, when a plasma current I is supplied to the reactorthrough the RF rod 15, the bridge 16, the first and second split points17 and 18, and the first through fourth feeds 19 through 22, across-talk occurs.

A direction of a plasma current I₁ flowing through an end portion of thefirst peripheral extending portion 16B of the bridge 16 may be oppositeto a direction of a plasma current I_(E1) flowing through the first feed19 and may be the same as a direction of a plasma current I_(E2) flowingthrough the second feed 20. Likewise, a direction of a plasma current I₂flowing through an end portion of the second peripheral extendingportion 16C of the bridge 16 may be opposite to a direction of a plasmacurrent I_(E3) flowing through the third feed 21 and may be the same asa direction of a plasma current I_(E4) flowing through the fourth feed22.

As such, as the plasma currents I₁ and I₂ flowing through the bridge 16and the plasma currents I_(E1) and I_(E3) flowing through the first feed19 and the third feed 21 flow in opposite directions, a cross-talkbetween currents may occur. Accordingly, the plasma currents I_(E1) andI_(E3) flowing through the first feed 19 and the third feed 21 and theplasma currents I_(E2) and I_(E4) flowing through the second feed 20 andthe fourth feed 22 may be different, thereby leading to RF electricfield (E-field) non-uniformity of plasma in the reactor. Thenon-uniformity may increase as a frequency of plasma increases.

FIG. 5 illustrates results of an experiment about uniformity of asilicon oxide film performed in each condition and an RF E-fielddistribution according to an arrangement of conductive structures fortransferring plasma.

(a) and (b) of FIG. 5 show E-field uniformity and thin film uniformitywhen plasma having 27.12 MHz and plasma having 60 MHz were applied to areactor including two feed RF rods. It is found that E-field uniformityand thin film uniformity when plasma having a frequency of 60 MHz wasapplied as shown in (b) of FIG. 5 are worse than those when plasmahaving a frequency of 27.12 MHZ was applied as shown in (a) of FIG. 5.That is, E-field uniformity and thin film uniformity deteriorate as aplasma frequency increases.

(c) and (d) of FIG. 5 show E-field uniformity and thin film uniformitywhen plasma having a frequency of 60 MHz was applied to a reactorincluding four feed RF rods, respectively corresponding to a case whereno ground shield was provided and a case where a ground shield wasprovided. In particular, it is found that, when a high frequency processof 60 MHz was used, RF E-field uniformity and thin film uniformity in(d) of FIG. 5 where a ground shield was inserted into 4-way feed RF rodsare much better than those in (b) and (c) of FIG. 5. That is, it isfound that a ground shield may control a cross-talk between plasmacurrents flowing through RF rods.

FIG. 6 is a perspective view of a plasma supply unit including four feedRF rods and a ground shield. FIG. 7 is a perspective view illustratingonly the ground shield GS of FIG. 6. The plasma supply unit and asubstrate processing apparatus including the plasma supply unitaccording to these embodiments may be a modification of the previousembodiments. Accordingly, a repeated description between embodimentswill not be given.

Referring to FIG. 6, the RF rod R of the plasma supply unit connected toa plasma generator (not shown) may be connected to the bridge 16, andthe bridge 16 and the plurality of feed RF rods F may be connected toeach other at the first and second split points 17 and 18. Accordingly,an RF current generated by the plasma generator may be supplied to areactor through the RF rod R, the bridge 16, the first and second splitpoints 17 and 18, feeds (marked by dashed lines), and the plurality offeed RF rods F. The plurality of feed RF rods F may be located symmetricabout the center of the substrate processing apparatus. For example, theplurality of feed RF rods F may extend to a gas supply unit (not shown)provided in the reactor, and extending portions may be located symmetricabout the center of the substrate processing apparatus.

The ground shield GS may be located between the bridge 16 and the firstthrough fourth feeds 19 through 22 (see FIG. 4A). The ground shield GSmay have an annular disk shape with a central hole. Also, optionally,the gas inlet 2 (see FIG. 9) connected to the gas supply unit may belocated through the central hole of the ground shield GS. In an optionalembodiment, the ground shield GS may include a plurality of panels, andthus the ground shield GS and the split points 17 and 18 may be easilycoupled to each other and the ground shield GS and the reactor may beeasily coupled to each other.

For example, as shown in FIG. 7, the ground shield GS may include afirst panel 25-1 and a second panel 25-2, and a ground shield structuresurrounding the gas inlet 2 may be formed by locating the first panel25-1 and the second panel 25-2 at both sides of the gas inlet 2 andassembling the first panel 25-1 and the second panel 25-2. However, theground shield GS may be integrally manufactured, or may be manufacturedas another form to be easily coupled with the split points 17 and 18and/or the reactor.

Although a cross-talk between the bridge 16 and the feeds (or the firstthrough fourth feeds) is prevented by inserting the ground shield GSbetween the bridge 16 and the first through fourth feeds (or the firstthrough fourth feeds) in the previous embodiments, the presentdisclosure is not limited thereto. The ground shield GS may extendbetween, for example, the first feed 19 (see FIG. 4A) and the third feed21 (see FIG. 4A). Alternatively, the ground shield GS may extend betweenthe first peripheral extending portion 16B and the second peripheralextending portion 16C of the bridge 16. Also, the ground shield GS mayextend between the feed RF rods F.

In other words, the ground shield GS may be located between the firstconductive portion C1 and the second conductive portion C2 that at leastpartially overlap each other, and thus a cross-talk that may occurbetween overlapping portions may be prevented, thereby improving overallE-field and film uniformity.

FIG. 8 is a schematic view of a substrate processing apparatus accordingto embodiments. The substrate processing apparatus according to theseembodiments may be a modification of the substrate processing apparatusaccording to the previous embodiments. Accordingly, a repeateddescription between embodiments will not be given.

Referring to FIG. 8, in the substrate processing apparatus, a reactionspace is formed when the reactor 1 and the substrate support 4 are inface contact or face-sealed. A substrate is mounted on the substratesupport 4, and a lower portion of the substrate support 4 is connectedto a device (not shown) that may be raised/lowered to load/unload thesubstrate.

The gas inlet 2 connected to the gas supply unit 3 is formed in thereactor 1. The gas inlet 2 may be formed by using a separate pipe, ormay be formed by forming a through-hole in the reactor 1. The plasmasupply unit P is located over the reactor 1. The plasma supply unit Pmay include a plasma generator (not shown), the RF rod R, the bridge 16,the first and third feeds 19 and 21, the feed RF rods F, and the groundshield GS.

The plasma supply unit P may be electrically connected to the gas supplyunit 3. In an embodiment, the plasma supply unit P may be electricallyconnected to the gas supply unit 3 through the RF rod R, the bridge 16,the first and third feeds 19 and 21, and the feed RF rods F. In moredetail, the feed RF rods F extending to the gas supply unit 3 may belocated at end portions of the first and third feeds 19 and 21. Forexample, the feed RF rods F may pass through the reactor 1 and may bemechanically connected to the gas supply unit 3. Also, the first andthird feeds 19 and 21 and the gas supply unit 3 may be electricallyconnected by the feed RF rods F, and as a result, the plasma supply unitP and the gas supply unit 3 may be electrically connected to each other.

A support member I is inserted between the feed RF rods F and thereactor 1, and the support member I is formed of an insulating material.Accordingly, the feed RF rod F (and the first or third feed 19 or 21connected to the feed RF rods F) and the reactor 1 may be electricallyinsulated from each other due to the support member I, therebypreventing plasma power from leaking during a plasma process.

FIG. 9 is a detailed view illustrating the plasma supply unit P of thesubstrate processing apparatus of FIG. 8. As shown in FIG. 9, the groundshield GS may be located between the bridge 16 and feeds (marked bydashed lines). Also, the ground shield GS may include a central holethrough which the gas inlet 2 is located, a through-hole T in which asplit point is located, and a through-hole T′ for connecting the groundshield GS and the reactor 1.

As described above, the split point may be provided in the through-holeT and the plasma supply unit P may be electrically connected to the gassupply unit 3, and the metal member M may be provided in thethrough-hole T′ and the ground shield GS may be electrically connectedto the reactor 1. Accordingly, a plasma component may flow from theplasma supply unit P through the bridge 16 and the first through fourthfeeds 19 through 22 to the gas supply unit 3, and a cross-talk may becontrolled by the ground shield GS located between the bridge 16 and thefeeds.

For brevity, a limited number of combinations of related features havebeen described. However, it will be understood that the feature of anarbitrary example may be combined with the feature of another example.Furthermore, it will be understood that these advantages are not limitedand specific advantages are not or are not required to be the feature ofa specific embodiment.

It will be understood that a shape of each portion in the attacheddrawings is illustrative for better understanding of the presentdisclosure. Accordingly, it will be understood that each portion may bemodified to have any of other shapes.

While one or more embodiments have been described with reference to thefigures, it will be understood by one of ordinary skill in the art thatvarious changes in form and details may be made therein withoutdeparting from the spirit and scope of the disclosure as defined by thefollowing claims.

What is claimed is:
 1. A substrate processing apparatus comprising: areactor; a gas supply unit located in the reactor; and a plasma supplyunit electrically connected to the gas supply unit, wherein the plasmasupply unit comprises: a first conductive portion; a second conductiveportion extending to overlap at least a part of the first conductiveportion; and a ground shield located between the first conductiveportion and the second conductive portion.
 2. The substrate processingapparatus of claim 1, wherein the second conductive portion extends tothe gas supply unit so that the second conductive portion and the gassupply unit are electrically connected to each other.
 3. The substrateprocessing apparatus of claim 1, further comprising: a radio frequency(RF) rod extending to the first conductive portion to electricallyconnect a plasma generator to the first conductive portion; and a coversurrounding the RF rod and electrically connected to the reactor,wherein an induced signal component generated by at least one of thefirst conductive portion and the second conductive portion flows throughthe ground shield, the reactor, and the cover.
 4. The substrateprocessing apparatus of claim 3, further comprising at least one metalmember configured to mechanically fix the ground shield to the reactor.5. The substrate processing apparatus of claim 1, wherein the groundshield has a plate-like structure, and comprises at least onethrough-hole through which the first conductive portion and the secondconductive portion are connected to each other.
 6. The substrateprocessing apparatus of claim 5, wherein the ground shield has anannular disk shape with a central hole, wherein a gas inlet connected tothe gas supply unit is located through the central hole of the groundshield.
 7. A substrate processing apparatus comprising: a gas inlet; agas supply unit connected to the gas inlet; and a plasma supply unitelectrically connected to the gas supply unit, wherein the plasma supplyunit comprises: a plasma generator; a radio frequency (RF) rod connectedto the plasma generator; a bridge connected to the RF rod and extendingto surround the gas inlet; a plurality of feeds located symmetric aboutthe gas inlet; and a split point configured to connect the bridge to theplurality of feeds.
 8. The substrate processing apparatus of claim 7,wherein the plurality of feeds comprise: a first feed having at least apart extending to overlap a first end portion of the bridge; a secondfeed extending in a direction opposite to a direction in which the firstfeed extends; a third feed having at least a part extending to overlap asecond end portion of the bridge; and a fourth feed extending in adirection opposite to a direction in which the third feed extends. 9.The substrate processing apparatus of claim 7, wherein the plasma supplyunit further comprises a ground shield located between the bridge andthe plurality of feeds.
 10. The substrate processing apparatus of claim7, further comprising a plurality of feed RF rods configured toelectrically connect the plurality of feeds to the gas supply unit,wherein the plurality of feeds and the plurality of feed RF rods arelocated symmetric about the gas inlet.
 11. A substrate processingapparatus comprising a plasma supply unit, wherein the plasma supplyunit comprises: a radio frequency (RF) rod; a bridge; a split point; aplurality of feeds; and a ground shield located between the bridge andthe plurality of feeds, and wherein the plasma supply unit is connectedto an upper portion of a reactor.
 12. The substrate processing apparatusof claim 11, wherein the RF rod and the bridge are connected to eachother, the bridge and the plurality of feeds are connected to each otherat the split point, and an RF current is supplied to the reactor throughthe RF rod, the bridge, the split point, and the plurality of feeds. 13.The substrate processing apparatus of claim 12, wherein the plurality offeeds are located symmetric about a center of the substrate processingapparatus.
 14. The substrate processing apparatus of claim 11, whereinthe ground shield comprises a metal.
 15. The substrate processingapparatus of claim 14, wherein the ground shield comprises aluminum. 16.The substrate processing apparatus of claim 11, wherein the groundshield is configured to prevent a cross-talk occurring between thebridge and the plurality of feeds.
 17. The substrate processingapparatus of claim 11, further comprising a plasma generator configuredto generate plasma having a frequency equal to or greater than 60 MHz.18. The substrate processing apparatus of claim 11, further comprising agas inlet located between the plurality of feeds connected to the upperportion of the reactor, wherein the bridge bypasses the gas inlet. 19.The substrate processing apparatus of claim 11, further comprising aplurality of feed RF rods configured to electrically connect theplurality of feeds to the upper portion of the reactor, wherein theplurality of feeds and the plurality of feed RF rods are locatedsymmetric about the upper portion of the reactor.